Magda: "Barnabas is my friend."
Aristede: "As well as your enemy."
The birth of the frenemy!
LOL.
As for Petofi and Tate's soul, since Petofi isn't the Devil and doesn't have his own hell to cast people into after they die, I never really considered that Andreas and/or CDT meant that literally. I imagine that whatever arrangement the two of them came to was a dirty one where Tate had to do some nasty things, selling his soul in the colloquial sense. If they said it was literal, then I'm showing initiative when viewing, adjusting what I hear a bit so that it makes sense and is consistent.
A lot of the discontinuities fans complain about are best dealt with in this way. Just regard a brief passing discontinuity as a slip of the tongue. Also taking characters absolutely literally can create discontinuity where none exists. That happens very often in all fandoms.